Problem: If $x \oplus y = 7x-y$ and $x \dagger y = xy+2x-y$, find $-3 \oplus (-2 \dagger -1)$.
Solution: First, find $-2 \dagger -1$ $ -2 \dagger -1 = (-2)(-1)+(2)(-2)-(-1)$ $ \hphantom{-2 \dagger -1} = -1$ Now, find $-3 \oplus -1$ $ -3 \oplus -1 = (7)(-3)-(-1)$ $ \hphantom{-3 \oplus -1} = -20$.